In manufacturing processes of semiconductor chips, dicing (individualization) processes cause significant stress in semiconductor wafers. Microcracks have thus occurred in semiconductor wafers which have led to high defect rates.
In order to prevent such a problem, applying a thermosetting adhesive sheet immediately before dicing (after backgrinding) to reinforce the semiconductor wafer has been proposed (for example, refer to PLT 1).
Furthermore, in order to ensure traceability for quality of semiconductor chips, it is desirable to laser-mark information such as a lot number on the thermosetting adhesive sheet. Still further, to enable accurate alignment, it is desirable to read alignment marks on the back surface of the semiconductor to which the thermosetting adhesive is applied.
However, to improve laser mark readability, in the case of adding a coloring agent to the thermosetting adhesive sheet, transparency is reduced and alignment mark readability might be problematic.